University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Ewa Bulska

Abbrev:
Bulska, E.
Other Names:
Address:
Department of Chemistry, University of Warsaw, Pastuera 1, Warsaw PL-02093, Poland
Phone:
NA
Fax:
+48 (22) 8225 996

Citations 10

"Critical Evaluation Of Analytical Performance Of Atomic Absorption Spectrometry And Inductively Coupled Plasma Mass Spectrometry For Mercury Determination"
Spectrochim. Acta B 2005 Volume 60, Issue 3 Pages 345-350
A. Krata and E. Bulska

Abstract: The analytical performance of cold vapor atomic absorption spectrometry (CV AAS), graphite furnace atomic absorption spectrometry (GF AAS) and inductively coupled plasma mass spectrometry (ICP-MS) for mercury determination have been investigated with the use of two reference materials SRM 2710 Montana I Soil and BCR-144R (sewage sludge from domestic origin). The digestion conditions and their influence on determination of mercury have been studied. Samples were decomposed by microwave digestion in closed vessels with the use of HCl alone or mixture of HCl+HNO3+HF. The digestion solutions were analyzed by CV AAS using NaBH4 as a reducing agent, by GF AAS with Pd or mixture of Pd/Rh as modifiers and by ICP-MS with Rh as internal standard. In the case of CV AAS, results were not dependent on digestion conditions. In the case of GF AAS and ICP-MS, results depended significantly on digestion conditions; in both cases, the use of the mixture of acids as defined above suppressed the signal of mercury. Therefore, in those cases, the microwave digestion with HCl is recommended. Detection limits of 0.003, 0.01 and 0.2 ?g g-1 were achieved by ICP-MS, CV AAS and GF AAS, respectively. © 2004 Elsevier B.V. All rights reserved.

"Secondary Ion Mass Spectrometry For Characterizing Antimony, Arsenic And Selenium On Graphite Surfaces Modified With Noble Metals And Used For Hydride Generation Atomic Absorption Spectrometry"
Spectrochim. Acta B 2002 Volume 57, Issue 12 Pages 2017-2029
E. Bulska, W. Jedral, E. Kopysca, H. M. Ortner and S. Flege

Abstract: The surface and sub-surface distribution of noble metals (after electrodeposition of 600 µg or thermal reduction of 10 µg as modifiers), as well as Sb, As and Se (200 ng) as analytes after their deposition on the graphite surface was investigated using secondary ion mass spectrometry (SIMS) in the dynamic mode. This permitted simultaneous observation of the depth profile distribution of modifier and analyte with a depth resolution of down to approximately 25 nm, limited however, by the surface roughness of the samples. Hydride generation was intentionally used for this purpose because in this approach the investigated system: graphite-modifier with added analyte is free from matrix components. This was essential for the evaluation of this novel approach using SIMS for surface analysis. Investigations concerning the distribution of analytes were performed on the graphite surface modified with palladium, iridium or rhodium. It was found that after deposition at 400°C, all analytes partially penetrated the graphite surface and their distribution overlaps the distribution pattern of the noble metals. The degree of penetration differs for each analyte and depends on the modifier used.

"Microcolumn Sorption Of Antimony(III) Chelate For Antimony Speciation Studies"
Spectrochim. Acta B 1999 Volume 54, Issue 5 Pages 873-881
Slawomir Garboš, Monika Rzepecka, Ewa Bulska and Adam Hulanicki

Abstract: Selective sorption of the Sb(III) chelate with ammonium pyrrolidinedithiocarbamate (APDC) on a microcolumn packed with C16-bonded silica gel phase was used for the determination of Sb(III) and of total inorganic Sb after reducing Sb(V) to Sb(III) by L-cysteine. A flow injection system composed of a microcolumn connected to the tip of the autosampler was used for pre-concentration The sorbed Sb was directly eluted with EtOH into the graphite furnace and determined by AAS. The detection limit for Sb was significantly lowered to 0.007 µg L-1 in comparison to 1.7 µg L-1 for direct injection GFAAS. This procedure was applied for speciation determinations of inorganic Sb in tap water, snow and urine samples. For the study of long-term stability of Sb species a flow injection hydride generation atomic absorption spectrometry with quartz tube atomization (FI HG QT AAS) and GFAAS were used for selective determination of Sb(III) in the presence of Sb(V) and total content of Sb, respectively. Studies on the stability of Sb in several natural samples spiked with Sb(III) and Sb(V) indicated instability of Sb(III) in tap water and satisfactory stability of inorganic Sb species in the presence of urine matrix.
Speciation Preconcentration Extraction

"Analytical Advantages Of Using Electrochemistry For Atomic Spectrometry"
Pure Appl. Chem. 2001 Volume 73, Issue 1 Pages 1-7
Ewa Bulska

Abstract: Atomic spectrometry and electrochemistry are usually recognized as independent analytical tools used for different purposes. Here, a brief review is given of the advantages of using electrochemistry in the various fields of atomic spectrometry techniques. In the first part, the application of electrochemical pre-concentration before the atomic spectrometry will be addressed and exemplified. Electrochemical pre-concentration could be used with flame atomic absorption spectrometry (AAS) or graphite furnace AAS as well as with atomic emission plasma sources. The second area of the applications of electrochemistry will be directly focused on the graphite furnace AAS where the electrodeposition onto the graphite surface of the atomizer could be used for both in situ analyte pre-concentration or modification of the surface by noble metals.

"Noble Metal Modifiers For Antimony Determination By Graphite Furnace Atomic Absorption Spectrometry In Biological Samples"
J. Anal. At. Spectrom. 2001 Volume 16, Issue 1 Pages 99-101
M. Wojciechowski, M. Piacik and E. Bulska

Abstract: The use of palladium, iridium or rhodium as a modifier in graphite furnace atomic absorption spectrometry was investigated for the determination of antimony in eluent fractions from high-performance liquid chromatography separation of clinical samples. The separation of albumin and transferrin at the physiological pH was carried out by ion chromatography on a Cosmogel DEAE column. As an eluent, 0.01 mol L-1 Tris-HCl in NaCl 1 mol L-1 gradient was used. Several fractions-of 0.5 mi each were collected and the concentration of antimony was determined off-line by GFAAS. Palladium, iridium and rhodium effectively stabilise antimony in an aqueous standard solution. In the presence of proteins, Tris-HCl buffer and NaCl, rhodium loses its stabilising performance. However, palladium and iridium were found to be efficient with respect to stabilisation of antimony up to 1500°C in matrix-containing solutions.

"Analytical Performance Of Solid Sorbents For Mercury Speciation"
Chem. Anal. 2002 Volume 47, Issue 3 Pages 429-437
A. Krata, E. Kopysc, K. Pyrzynska and E. Bulska

Abstract: Several solid sorbents (Dowex 50Wx4, Amberlyst A-27, C-16 and Chelex 100) were tested in respect to their efficiency of sorption and elution of inorganic and organic mercury compounds. It was found that both forms of mercury could be effectively trapped by all investigated sorbents. However the selective elution of organic and inorganic mercury compounds by 0.1% thiourea in 3% or 8% HCl was achieved with the use of Dowex 50Wx4. The detection limit for Hg2+ and PhHg+ was 0.013 mg L-1 and 0.075 mg L-1 respectively. The precision of the determination was 5.2% at the level close to detection limit, and 0.8% at the level of 50 mg L-1. The developed procedure, based on the retention of both mercury species and their sequential elution, was tested by analysis of the springly water spiked with known amount of Hg2+ and PhHg+.

"Determination Of Antimony(III) By Flame AAS After Microcolumn Preconcentration On DETA Sorbent"
Atom. Spectrosc. 2000 Volume 21, Issue 4 Pages 128-131
Garbos, S.;Bulska, E.;Hulanicki, A.

Abstract: Selective sorption of Sb(III) on a microcolumn packed with DETA sorbent with grafted diethylenetriamine groups in a flow injection (FT) system was used for the determination of Sb(III) by flame atomic absorption spectrometry (FAAS). The sorbed antimony was directly eluted with HNO3 and determined on-line by FAAS. The detection limit of FI-FAAS procedure for antimony was 0.9 µg/L (3s) and was comparable to 0.8 µg/L for the direct injection GFAAS. The precision of the Sb determination (relative standard deviation, n=5) at the concentration level of 10 µg/L was 5.2%. Since total antimony was directly determined by graphite furnace atomic absorption spectrometry (GFAAS), the Sb(V) concentration could be calculated by the difference. The FI-FAAS procedure and GFAAS technique were applied for speciation determination of inorganic antimony in spiked oligocene water sampled from a well, which reaches the layer of rocks formed during the oligocene period.

"Determination Of Mercury By Cold-vapor Atomic Absorption Spectrometry With Preconcentration On A Gold-trap"
Anal. Sci. 2000 Volume 16, Issue 12 Pages 1309-1312
Edyta KOPYSC, Krystyna PYRZYNSKA, Sawomir GARBOS, and Ewa BULSKA

Abstract: The determination of trace levels of mercury by flow injection cold-vapor atomic absorption spectrometry with gold amalgamation was evaluated for organic and inorganic mercury species. The effect of the sodium tetrahydroborate(III) and hydrochloric acid concentrations as well as various instrumental parameters on the analytical performance was studied. The influence of the blank as well as the laboratory procedure for reagent purification was evaluated. The procedure was applied to the determination of mercury in lake water, while focusing on the importance of the sampling protocols.

"Online Preconcentration Of Lead And Cadmium For Flame Atomic Absorption Spectrometry Using A Flow-through Electrochemical Microcell"
Anal. Chim. Acta 1997 Volume 357, Issue 1-2 Pages 133-140
Ewa Bulska*, Maciej Wa

Abstract: A method was developed for the trace determination of lead and cadmium by flame atomic absorption spectrometry (FAAS) with electrochemical pre-concentration. Both metals were deposited on the glassy-carbon electrode in a flow-through microcell of volume 3 µL. At a consumption of a 3 µL sample volume, the procedure resulted in an enhancement factor of more than 20 and yielded a detection limit of 1 µg L-1 for Pb and 0.08 µg L-1 for Cd. The relative standard deviation (n=12) was 2.1% at the 100 µg L-1 level for Pb and 3.2% at the 8 µg L-1 level for Cd. Results obtained for the standard reference material, water SRM 1643 c, were in good agreement with the certified values.
Lead Cadmium Spectrophotometry Preconcentration Electrochemical stripping

"Use Of Solid-phase Extraction To Eliminate Interferences In The Determination Of Mercury By Flow-injection CV AAS"
Anal. Bioanal. Chem. 2003 Volume 377, Issue 4 Pages 735-739
Agnieszka Krata, Krystyna Pyrzyńska and Ewa Bulska

Abstract: Solid-phase extraction with two-step elution has been developed for effective elimination of copper and iron interference with mercury determination by flow-injection cold vapor atomic absorption spectrometry (CV AAS). Sodium tetrahydroborate(III) was used as reducing agent. Cation-exchanger Dowex 50Wx4 was applied for the sorption of mercury and both interfering ions. In the first step elution of Cu(II) and Fe(III) was performed using 0.5 mol L-1 KF solution. Then mercury was eluted with 0.1% thiourea in 8% HCl. The detection limit (3s) for Hg(II) was 27 ng L-1. The expanded uncertainty estimated for the whole procedure was about 6%. The accuracy of the proposed method was evaluated by determination of the recovery of known amount of mercury added to mineral, spring, and tap waters, and by analysis of a certified reference material BCR-144R (sewage sludge).
Mercury BCR 144 Mineral Spring Water Spectrophotometry Solid phase extraction Dowex Interferences